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| Potency relative to Hydrocortisone |
Half-Life | ||||
| Equivalent Glucocorticoid Dose (mg) | Anti- Inflammatory |
Mineral- Corticoid |
Plasma (minutes) |
Duration of Action (hours) | |
| Short Acting | |||||
| Hydrocortisone (Cortef, Cortisol) |
20 | 1 | 1 | 90 | 8-12 |
| Cortisone Acetate | 25 | 0.8 | 0.8 | 30 | 8-12 |
| Intermediate Acting | |||||
| Prednisone | 5 | 4 | 0.8 | 60 | 12-36 |
| Prednisolone | 5 | 4 | 0.8 | 200 | 12-36 |
| Triamcinolone | 4 | 5 | 0 | 300 | 12-36 |
| Methylprednisolone | 4 | 5 | 0.5 | 180 | 12-36 |
| Long Acting | |||||
| Dexamethasone | 0.75 | 30 | 0 | 200 | 36-54 |
| Betamethasone | .6 | 30 | 0 | 300 | 36-54 |
| Mineralocorticoid | |||||
| Fludrocortisone | 0 | 15 | 150 | 240 | 24-36 |
| Aldosterone | 0 | 0 | 400 + | 20 | - - |
| Reference: Adrenal Cortical Steroids. In Drug Facts and Comparisons. 5th ed. St. Louis, Facts and Comparisons, Inc.:122-128, 1997 | |||||
Commonly Prescribed Replacement Steroid Equivalents
| Prednisone | Cortisone | Dexamethasone | Hydrocortisone (Cortef) | |||
| 5 mg | = | 25 mg | = | 0.75 mg | = | 20 mg |
Click here for a PDF of this chart.
A defect at any point along the hypothalamic-pituitary-adrenal (HPA)-axis could disrupt normal physiologic glucocorticoid levels. Administration of exogenous glucocorticoids leads to suppression of cortisol production by the adrenal cortex.
HPA-axis suppression is a well-known adverse effect of glucocorticoid therapy; however, considerable controversy exists over the dose and duration of glucocorticoid therapy required to suppress the HPA-axis.
Some of the many factors that influence HPA-axis suppression include time of day that the doses are administered, route of administration, dose and duration of therapy, and duration of action of the agent used.
Reference: Helfer EL, Rose LI. Corticosteroids and adrenal suppression: characterizing and avoiding the problem. Drugs. 1989;38(5):838-845
Hormone production by the adrenal gland is influenced by many factors. Normal cortisol production follows a diurnal cycle. Levels peak in the early morning hours (6 am–8 am) and decline throughout the day with a second, lower peak in the late afternoon (4 pm–6 pm).
In an adult who is not experiencing stress, the average amount of cortisol secreted by the adrenal gland is equivalent to 5 mg of prednisone.
Reference: Katzung BG. Basic and Clinical Pharmacology. 6th ed. East Norwalk: Appleton & Lange;1995:590-607
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